I don't see a problem with her moving in with you. I would talk to your friend about it though, just to let him know, and that you two are still kewl and such. About the girl, I would wait for her to come around, I say this cause I don't know how much she liked him, but I would wait accordingly to her "mourning peroid" and not interrupt it. Call me pathetic. Maybe she isn't sad at all and ready to move on, and if she is, I say go for it. Only love once.
Whiskey
Whiskey